soc: qcom: smem: verify both host ids in partition header

The global partition is indicated by having both host values in its
table of contents entry equal SMEM_GLOBAL_HOST=0xfffe.

In qcom_smem_set_global_partition(), we check whether the header
structure at the beginning of the partition contains that host
value, but the check only verifies *one* of them.  Change the check
so the partition header must have SMEM_GLOBAL_HOST for *both* its
host fields.

Signed-off-by: Alex Elder <elder@linaro.org>
Signed-off-by: Andy Gross <andy.gross@linaro.org>